A receiver is a crucial component in an analog TV system and environment. In the prior art, a receiver of an analog TV performs signal demodulation via an analog approach, and a typical hardware structure as illustrated in FIG. 1. An analog TV receiver 10 comprises a radio frequency (RF) tuner 11, a surface audio wave (SAW) filtering circuit 12, a programmable gain amplifier (PGA) 13, an analog demodulator 14, and analog-to-digital converters (ADCs) 15 and 16 for sending signals to other components, such as decoders. The RF tuner 11 converts an analog RF TV signal received by an antenna 111 to an analog IF TV signal. The SAW filtering circuit 12 filters out noises of the analog IF TV signal. The PGA 13 amplifies the noises-removed analog IFTV signal to a desired intensity. The analog demodulator 14 demodulates the amplified analog IF TV signal to generate an analog composite video broadcast signal (CVBS) and a sound intermediate frequency (SIF) signal, which are respectively converted by the ADCs 15 and 16 to digital signals to be respectively transmitted to a video decoder and an audio decoder for subsequent digital signal processing or rendering. However, the effect of analog demodulation is not always ideal, and may seriously affect quality of a TV signal. Therefore, there is a need in the art to increase demodulation efficiency and improve the generation of digital TV signals.